I have to convert the audio tracks of my 24 fps movie to match up with retimed 25fps so that it can be exported alongside the 25fps video (just playback speed change) for broadcast transmission.
I need to speed up the audio to match the new shorter duration (96% of the original speed) while keeping the quality of voice, effects and all the other things as high as possible and with the same pitch.
1) My source audio is 5.1 and it needs to be stereo for broadcast. To keep maximum quality, should I do the mixdown or the retime first? Does it matter?
First mixdown to stereo still at 24fps and only after shrink the audio to 25fps duration right ? I'm not asking how to mixdown, I know how to do it, just asking in what order.
2) Do I need a VST plugin to get good results or can Audition achieve good results directly?
A professional I know in the industry had said he had issues getting decent quality results out of Audition and I wasn't sure if a VST plugin might do a better job.
3) If it is possible to do with Audition directly, what are the proper settings for using Audition?
I think I should go for the Effects -> Stretch and Pitch effect (the one in the picture). My duration will be the original * 0.96.**
What other settings I should check inside that plugin ?
-> Algorithm: iZotope Radious or Audition ? -> Lock Stretch Settings to New Duration ? -> Vocoder Mode ? -> Solo Instrument or Voice ? -> Preserve Speech Characteristics ? -> Formant Shift ??? -> Pitch Coherence ???
Could you explain why you pick some settings and not others?
4) Does it matter if I apply the effect selecting all the channels together or do some changes need to be made on individual channels?
I'm concerned about producing panning artifacts, but my guess is to apply the effect to all the channels at same time.